How B-Type Natriuretic Peptide (BNP) and Body Weight Changes Vary in Heart Failure With Preserved Ejection Fraction Compared With Reduced Ejection Fraction: Secondary Results of the HABIT (HF Assessment With BNP in the Home) Trial.

BACKGROUND: Heart failure is a common cause of hospitalization and can be divided into types with preserved and reduced ejection fraction (HFpEF and HFrEF, respectively). In this subanalysis of the HABIT (Heart Failure Assessment With BNP in the Home) trial, we examined the differences between home B-type natriuretic peptide (BNP) testing and weight monitoring in patients with HFpEF and with HFrEF before decompensation. METHODS AND RESULTS: This was a retrospective review of patients with HFpEF and HFrEF from the HABIT trial. The HFpEF patients compared with HFrEF patients were older and more obese and had lower baseline BNP values. Intra-individual BNP dispersion (spread of distribution over time) was greater in HFpEF than in HFrEF owing to rapid fluctuations (within 3 days). Slowly varying changes in BNP (estimated by a moving average) were equally predictive of ADHF risk in both HFpEF and HFrEF. However, in HFpEF, a rapid rise in BNP >200 pg/mL within 3 days was associated with an increased risk of acute decompensated heart failure (ADHF; hazard ratio 4.0), whereas a similar association was not observed in HFrEF. Weight gain ≥5 lb in 3 days had a high specificity but low sensitivity for ADHF in both HFpEF and HFrEF, whereas a lower threshold of ≥2 lb weight gain over 3 days in patients with HFpEF (but not HFrEF) was a moderately sensitive cutoff associated with decompensation (60% sensitivity). CONCLUSIONS: Patients with HFpEF and HFrEF have variations in their BNP and weight before decompensation. The rapid time scale behaves differently between the groups. In those with HFpEF, a 3-day period characterized by ≥2 lb weight gain and/or >200 pg/mL BNP rise was significantly associated with decompensation. Future prospective studies investigating different weight and BNP cutoffs for home monitoring of HFpEF and HFrEF patients should be performed to fully learn the value of BNP changes before clinical deompensation.

Myeloperoxidase in the diagnosis of acute coronary syndromes: the importance of spectrum.

BACKGROUND: Myeloperoxidase (MPO) is proposed for risk stratification in patients with suspected acute coronary syndromes (ACSs). We determined if MPO has diagnostic value in patients being evaluated for ACS. METHOD: MIDAS was an 18-center prospective study enrolling suspected ACS emergency department patients who presented <8 hours after symptom onset and in whom serial cardiac markers and objective cardiac perfusion testing were planned. Blinded MPO (Biosite, Inc, San Diego, CA) and troponin I (Triage Cardio 3; Biosite, Inc) were drawn at arrival, and Troponin I (TnI) was measured at 90, 180, and 360 minutes. Final diagnoses were adjudicated by the local investigator blinded to study assay. RESULTS: Of 1,018 patients, 54% were male, 26% black, with a mean age of 58 ± 13 years. Diagnoses were ACS in 288 (23%) and noncardiac chest pain (NCCP) in 788 (77%). Of patients with ACS, 94 (9.2%) had a myocardial infarction (MI) at presentation (69 non-ST-elevation MI, 25 ST-elevation MI), and 136 had unstable angina. Using a cutpoint of 210 ng/mL to provide 90% specificity, MPO had a sensitivity of 0.18; negative predictive value, 0.69; positive predictive value, 0.47; negative likelihood ratio, 0.91; and a positive likelihood ratio of 1.83 to differentiate ACS and NCCP. Because of the large overlap of quartiles, MPO was not clinically useful to predict serial TnI changes. The C statistics ± 95% CI for MPO differentiating ACS from NCCP and for AMI versus NCCP were 0.629 ± 0.04 and 0.666 ± 0.06, respectively. CONCLUSIONS: Myeloperoxidase has insufficient accuracy for decision making in patients with suspected ACS.

Daily home BNP monitoring in heart failure for prediction of impending clinical deterioration: results from the HOME HF study.

BACKGROUND: Serial measurement of natriuretic peptides may guide management in heart failure (HF) patients. In previous trials, natriuretic peptides were infrequently monitored, which may undervalue the benefit of this approach. METHODS AND RESULTS: HOME was an adaptive three-arm randomized clinical study to test whether home monitoring of BNP could reduce HF-related death, hospitalization due to acute decompensated HF (ADHF), and ADHF treated with intravenous diuretics in the emergency department or outpatient setting. Enrolment was terminated early because of slow enrolment, low event rates, and the belief that an algorithm for assessing BNP trends was needed. Justification for pooling data from all study arms was made and analysis as a single observational study was performed. The analysis resulted in 107 patients who were monitored for a median of 172 days with BNP measures on a median of 74% of days. BNP values were highly variable within a patient. Dispersion between serial BNPs was calculated to be 39.3%, 57.7%, and 73.6% for 1, 60, and 120 days between measures, respectively. A moving average filter (fBNP) was calculated to reduce day-to-day fluctuations and track changes from week to week. There were 27 primary events in 17 362 patient days of monitoring; the hazard ratio for time-varying fBNP was 2.22 (95% confidence interval 1.48-3.34) per unit natural log (corresponding to a 2.72-fold change in fBNP level). CONCLUSION: The HOME HF study demonstrates the feasibility of home BNP measurement and shows the potential value of fBNP as an index of emerging clinical deterioration. Assessment of the clinical value of this is required.

Primary results of the HABIT Trial (heart failure assessment with BNP in the home).

OBJECTIVES: This study was a multicenter, single-arm, double-blinded observational prospective clinical trial designed to monitor daily concentrations of B-type natriuretic peptide (BNP) and to determine how these concentrations correlate with acute clinical heart failure decompensation (ADHF) and related adverse clinical outcomes in at-risk HF patients. BACKGROUND: Although BNP at discharge is predictive of 30-day outcomes, outpatient serial testing may improve the risk of detecting early decompensation. METHODS: A total of 163 patients with HF signs and symptoms of ADHF discharged from the hospital or in an outpatient setting measured their weight and BNP levels daily for 60 days with a finger-stick test. Patients and physicians were blinded to BNP levels. The composite outcome was ADHF events: cardiovascular death, admission for decompensated HF, or clinical HF decompensation requiring either parenteral HF therapy or changes in oral HF medications. RESULTS: A total of 6,934 daily BNP values were recorded, with a median of 46 measures per patient over a monitoring period of 65 days. Forty patients had 56 events. Correlations between BNP measures weakened over time, and the dispersion between BNP measures grew. During 10,035 patient-days, there were 494 (4.9%) days of weight gain (≥5 lbs). The hazard ratio per unit increase of ln BNP was 1.84, and the hazard ratio on a day of weight gain was 3.63. These effects retained significance when controlling for symptoms. When the monitoring period for each subject was broken into intervals based on ADHF events, there were 39 (18.4%) intervals of upward trending BNP corresponding to a risk increase of 59.8% and 64 (30.2%) downward trending intervals corresponding to a risk decrease of 39.0%. There were 94 (44.3%) intervals with 1 or more days of weight gain corresponding to a risk increase of 26.1%. CONCLUSIONS: This pilot study demonstrates that home BNP testing is feasible and that trials using home monitoring for guiding therapy are justifiable in high-risk patients. Daily weight monitoring is complementary to BNP, but BNP changes correspond to larger changes in risk, both upward and downward. (Heart Failure [HF] Assessment with B-type Natriuretic Peptide [BNP] In the Home [HABIT]; NCT00946231).

A single rapid point-of-care placental growth factor determination as an aid in the diagnosis of preeclampsia.

OBJECTIVES: To evaluate the clinical performance of a rapid point-of-care test, Triage PLGF (Alere, San Diego) in the diagnosis of preeclampsia. STUDY DESIGN: For the reference range 2212 plasma samples were collected from 595 subjects with normotensive pregnancies, between week 17 of gestation and delivery. In the case-control part, two cohorts of women with preeclampsia (80 women) were matched for maternal age, gestational age (GA) at sampling and parity with normotensive women who delivered at 37weeks or more. RESULTS: The areas under the receiver operating characteristic curves (GA<35weeks) were 1.0 and 0.994 (cohort 1 and 2, respectively). The clinical sensitivity of the Triage PLGF test for the pooled GA range of 21⩽GA<35, using a GA dependent cut-off, was 1.0 for both cohorts with specificities of 1.0 and 0.940. CONCLUSIONS: The Triage PLGF test distinguishes well between preterm pregnancies with and without preeclampsia.